A positioning apparatus for holding a workpiece which is to undergo working (referred to below simply as a workpiece) and optimizing the position and attitude of the workpiece to a robot for carrying out working is sometimes used when carrying out working operations such as assembly or welding using robots and the like.
Such a positioning apparatus makes it possible to perform working operations on various portions of a workpiece within a smaller workspace using a robot for working operations.
This positioning apparatus is, for example, used in a master/slave robot system in which a workpiece is held at the end of a robot and working is carried out while positioning the workpiece to a working robot.
However, the heavier the workpiece is, the larger output of actuators of the positioning apparatus is required, and hence the dimensions of the positioning apparatus become large.
Therefore, Patent Document 1 discloses a technique for positioning a workpiece in which a plurality of robots are controlled in concert and hold a heavy workpiece. Since the plurality of robots together hold a single workpiece, the power required for each robot decreases. Therefore, the positioning apparatus has a lower cost and takes up less space than when using a single robot having a higher carrying ability.